Uneven ground can make the use of chairs, tables, or other platforms greatly strained or even impossible. Because sitting locations are not always on flat ground, traditional chairs with legs of equal length can have uneven footing on rocky or unstable surfaces. Moreover, even if a traditional chair can maintain an even footing, the ground on which it sits may be sloped to a great enough degree that its use could be uncomfortable.
Although certain systems exist for extending and retracting rigid members, such as camera stands and other types of platforms, those systems are cumbersome and often require the user to operate the system with two hands or to expend greater amounts of force and energy than comfortable for their operation. Such cumbersome systems have also been employed in other applications of extending and retracting rigid members, such as the heightening of bicycle seats. Many of these systems also prevent motion in more than one direction, making a complete disengagement of the rigid member necessary to move the rigid member in any direction.